Three-dimensional (3-D) printing, also known as additive manufacturing, is a rapidly growing technology area that operates by depositing small droplets or streams of a melted or solidifiable printing material in precise deposition locations under control of a computer. Deposition of the printing material results in gradual, layer-by-layer buildup of an object, which can be in any number of complex shapes. Printing materials that can be used in three-dimensional printing include polymers and other solidifiable substances.
One of the shortcomings associated with conventional three-dimensional printing methods is incomplete fusion of the melted or solidifiable printing material within the printed object. As used herein, the term “fusion” will refer to the consolidation of a deposited printing composition to form a coherent structure. The terms “fusion” and “consolidation” may be used synonymously herein. Incomplete fusion of the printing material can be especially prevalent between adjacent layers of a printed object, which can result in structural weak points. In addition to producing structural weakness, incomplete fusion of the printing material can convey surface roughness to printed objects on at least a microscopic level, thereby resulting in a “pixelated” appearance under magnification. Presently, there are no effective ways to repair or post-process printed objects in order to rectify these issues. In contrast, traditional manufacturing techniques, such as molding and/or machining, generally form objects that are more homogenous in nature, contain fewer structural weak points, and have a smoother surface morphology.
Despite their shortcomings, objects produced by conventional three-dimensional printing methods can often be sufficient for rapid prototyping purposes. In this regard, prototypes having a variety of shapes and sizes can be produced, and tolerances are usually limited only by the size of the printer's deposition nozzles. Rapid production of prototypes represents a significant strength of three-dimensional printing, and there is concurrent interest in applying printing methods for mass manufacturing. For mass manufacturing purposes, however, the aforementioned defects resulting from incomplete fusion during printing can problematic, particularly for producing high-performance and/or exacting-tolerance objects with a desired degree of durability and quality. Although incomplete fusion can be mitigated somewhat by reducing the size of the deposition nozzles, albeit at the drawbacks of increased printing times and associated higher costs, there is currently no way to fully address the issue of poor fusion during three-dimensional printing.
In view of the foregoing, increasing the extent of fusion within printed objects would be of significant interest in the art. The present disclosure satisfies the foregoing need and provides related advantages as well.